Electrode holder construction for electric smelting furnaces



Aug. 16, 1960 A. H. INGELSRUD ETAL ELECTRODE HOLDER CONSTRUCTION FORELECTRIC SMEILTING FURNACES Filed Aug. 29, 1958 FIG. 2.

INVENTORS. ARNE HILDOR INGELSRUD 8 NILS JOHAN HAAVIK 6?zz,%m sel 1 vATTORNEYS United States Patent 9 ELECTRODE HOLDER CONSTRUCTION FORELECTRIC SMELTING Arne Hildor Inglsrud and 'Nils .Iohan Haavik, 'Oslo,

Norway, assignors to :Elektrokemisk A/S, Oslo, Norway, a corporation ofNorway Filed Aug. 29, 1958, set No. 758,137

Claims priority, application Norway Sept. 11, 1957 '4 Claims. (Cl. 1316)The present invention relates to a holder for electrodes, particularlyelectrodes of a continuous type which can be made substantiallycylindrical in shape and of relatively small increased diameter ascompared with the electrode in itself so that the clamp may be loweredthrough the furnace roof of a closed electric furnace. In the copendingapplication Serial No. 727,947 filed April 11, 1958, conical discsprings are used, but in this case we show a diiferent method ofcontrolling the pressure on such springs and a different manner in whichsuch pressure is transmitted to the electrode clamp itself. Here also weuse a pair of springs, but the number is not critical, and they can beof any resilient construction including not only disc but also coilsprings.

In accordance with this invention we use a pressure ring made up of aseries of interconnected units and with each unit of the pressure ringat least one clamp memher is provided. The pressure is transmitted fromthe pressure ring to the clamp members by means of springs, which in thecase of disc springs as shown in the drawings, are compressed togetherat their center. A bushing passes through the center of each pressurering unit and each bushing carries a pressure bolt. Means are providedso that the position of the pressure bolt relative to the bushing may beadjusted. This may be by means of fluid pressure which will permitadjustment from a remote point but an even simpler method is to have thepressure bolt screwed into the bushing. In such case means should beprovided to prevent the bushing rotating in the pressure ring sectionas, for example, by having a flat side on the bushing or by use of a keyway or the like.

This invention may be readily understood by reference to theillustrative example shown in the accompanying drawings in which Fig. 1is a horizontal section through a portion of the pressure ring, and oneof the electrode clamps; and

Fig. 2 is a vertical section taken under slightly different conditions.

The electrode is indicated at and it is understood that this is of thenow well known continuous type which is ordinarily provided with anoutside metal sheath. Fitting against the outside of the electrode 10 isa series of clamping members indicated at 12 which preferably are watercooled. Near its center each clamp member 12 has an insert 14 ofinsulating material.

The pressure ring is made up of a series of members designated by thenumeral 16 which are water cooled and interlocked at their ends with apin 18 passing through the interlocking hinge portions as shown inFig. 1. Similar interlocking pressure ring sections and the supportmechanisms, water connections and the like are shown for example in US.Patent No. 2,673,227. Each section 16 has a circular recess 20 in Whichare positioned a pair of conical disc springs 22 which are heldseparated at their peripheries by a ring 24. A bushing '26 slides in around central hole through each of the sections 16. This bushing 26 hasa collar 28 which contacts an inner portion of the pair of disc springs22. Threaded into the bushing 26 is a pressure bolt 30 preferablyhavinga rounded end adapted to contact with the insulation material 14.'The outer end of the bolt 30 has a centrally formed'recess, theinnerportion of which is threaded internally as indicated at 32 and theouter portion is squared 'as indicated at 34 so that it can receive asquared end wrench. A removable cover plate 36 is used to cover theouter end of the hole in which the bushing 26 moves.

In assembling the device the clamps 12 are placed around the electrodeand the pressure ring put around the outside of the clamps. The coverplates 36 are removed and by an appropriate Wrench the pressure bolts 30are screwed in until their inner ends contact the insulation material14. This screwing in is then continued, generating back pressure on thedisc springs 22, until the desired pressure is obtained to support theelectrode. Obviously this pressure may be varied as desired by screwingthe pressure bolts in or out in their respective bushings.

In some instances, as for example, when the pressure against theelectrode is to be released during displacement of the electrode, thiscan be accomplished in the manner illustrated in Fig. 2. In this casecover plate 36 is removed and a rod 38 is screwed into the innerthreaded portion 3'2 of the aperture in the end of the pressure bolt.Each rod 38 is supplied with a washer 4t) and carries a nut 42. Bytightening up the nut 42 the bushing and pressure bolt aresimultaneously drawn outwardly, compressing the disc springs 22 andeliminating all pressure against the clamp members 12. It will be notedin this case that when the nuts 14 are loosened the same pressure willbe exerted against the electrode as had previously been established andno readjustment of this pressure will be needed. It will be understoodthat the bushing 26 is held against rotation relative to the ringsection 16 in any convenient way as, for example, by a key 44. Inordinary operation the cover plates 36 should be kept in place toprevent accumulation of dust and the like around the outer ends of thebushings and pressure bolts.

It will be noted that with this construction if a disc spring isdestroyed, for example by action of heat, the necessary clamp pressureon the electrode can be maintained by means of the bushing and boltalone. This pressure will not be resilient but immediate interruption ofoperation is avoided and replacement of the spring can be postponeduntil a suitable occasion.

It is understood that the example given is intended only by way ofillustration and that the same may be modified in many particularswithout departing from the spirit of our mvention.

What we claim is:

1. An electrode holder for use with continuous electrodes in an electricsmelting furnace, the combination of a pressure ring made up ofinterconnected sections, at least one electrode clamp member for eachsuch section, a spring interposed between each clamp member and itspressure ring section, a bushing passing through the center portion ofeach pressure ring section tensioned by said spring toward the clampingmember, a pressure bolt carried by the bushing arranged to press againstthe clamping member means for adjusting the position of said bolt insaid bushing so that the pressure against the clamping member may beadjusted and means whereby said bushing and said pressure bolt may bemoved outwardly away from the clamping member without relative movementbetween the pressure bolt and the bushing.

2. A structure as specified in claim 1 in which disc springs are used.

3. A structure as specified in claim 1, in which the pressure bolt isthreaded in the bushing and is arranged to 'be screwed in or out throughthe bushing.

4. A structure as specified in claim 1, in which said pressure bolt'isformed with a threaded recess in its outer end and a rod is includedhaving a threaded end which can be screwed into said threaded recess,said rod carrying a washer that can press against the face of thepressure ring and having a threaded outer end that passes through thewasher and the nut on the outer end of such rod whereby when said rod isscrewed into the pressure bolt said nut may be tightened up to draw saidpressure bolt and the bushing outwardly.

References Cited in the file of this patent UNITED STATES PATENTSGermany Mar. 14, 1935

